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Enantioselective Catalysis of the Hetero‐Diels–Alder Reaction between Brassard's Diene and Aldehydes by Hydrogen‐Bonding Activation: A One‐Step Synthesis of ( S )‐(+)‐Dihydrokawain
Author(s) -
Du Haifeng,
Zhao Dongbo,
Ding Kuiling
Publication year - 2004
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200400515
Subject(s) - enantioselective synthesis , catalysis , diene , chemistry , yield (engineering) , hydrogen bond , solvent , lactone , toluene , organic chemistry , molecule , materials science , natural rubber , metallurgy
The first catalytic enantioselective hetero‐Diels–Alder reaction between Brassard's diene and aldehydes has been achieved through hydrogen‐bonding activation using TADDOL derivatives as catalysts to afford the corresponding δ‐lactone derivatives in moderate‐to‐good yields and with high enantioselectivities (up to 91 % ee ). The reactions can be carried out either under solvent‐free conditions or in toluene. On the basis of the absolute configurations of the products and the hydrogen‐bonding interaction pattern between TADDOL (α,α,α′,α′‐tetraaryl‐1,3‐dioxolan‐4,5‐dimethanol) and the carbonyl group disclosed by X‐ray diffraction analysis, a possible mechanism for the catalytic reaction has been proposed. To demonstrate the usefulness of the methodology, a natural product, ( S )‐(+)‐dihydrokawain, has also been prepared in 50 % isolated yield and with 69 % enantioselectivity in one step starting from 3‐phenylpropionaldehyde by using this methodology. Therefore, this catalytic system is one of the most direct approaches to the construction of δ‐lactone units, which will make the methodology very attractive for the synthesis of a variety of biologically important compounds and natural products.